Exhaust gas purification system of working machine

• US 8,844,273 B2
• Filed: 04/28/2011
• Issued: 09/30/2014
• Est. Priority Date: 05/07/2010
• Status: Expired due to Fees

• Current Assignee: Yanmar Power Technology Co., Ltd. (Yanmar Holdings Co., Ltd.)
• Original Assignee: Yanmar Company Limited (Yanmar Holdings Co., Ltd.)
• Inventors: Noma, Yasuo, Togashi, Taichi
• Primary Examiner(s): Denion, Thomas
• Assistant Examiner(s): Singh, Dapinder
• Application Number:
  US13/695,898
• Publication Number:
  US 20130067895A1
• Time in Patent Office: 1,251 Days
• Field of Search: 602/85, 602/86, 602/95, 602/97, 603/11
• US Class Current: 60/295
• CPC Class Codes: F01N 11/002 the diagnostic devices measuring or estimating temperature or pressure in, or downstream of the exhaust apparatus
• CPC Class Codes: F01N 13/0097 the purifying devices are arranged in a single housing
• CPC Class Codes: F01N 2240/36 an exhaust flap
• CPC Class Codes: F01N 2550/04 Filtering activity of particulate filters
• CPC Class Codes: F01N 3/023 using means for regenerating the filters, e.g. by burning trapped particles by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 3/0231 using special exhaust apparatus upstream of the filter for producing nitrogen dioxide, e.g. for continuous filter regeneration systems [CRT]
• CPC Class Codes: F01N 3/0235 using exhaust gas throttling means
• CPC Class Codes: F01N 3/103 Oxidation catalysts for HC and CO only
• CPC Class Codes: F02D 2200/101 Engine speed
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: F02D 31/001 Electric control of rotation speed
• CPC Class Codes: F02D 41/0245 by increasing temperature of the exhaust gas leaving the engine
• CPC Class Codes: F02D 41/029 the exhaust gas treating apparatus being a particulate filter
• CPC Class Codes: F02D 41/402 Multiple injections
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An exhaust gas purification device arranged in an exhaust system of an engine, and includes a renewing device for burning and removing a particulate matter within the exhaust gas purification device. The renewing device is operable in the case that a clogged state of the exhaust gas purification device is equal to or more than a prescribed level, wherein the exhaust gas purification system includes renewal admittance input means which allows an actuation of the renewing device, and rotating speed holding input means for holding a rotating speed of the engine to a predetermined rotating speed, and in the case that a turn-on operation of the rotating speed holding input means is carried out in a state in which an allowing operation of the renewal admittance input means is carried out, the rotating speed holding motion of the engine is executed in preference to an actuation of the renewing device.

Claims

1. An exhaust gas purification system of a working machine having an engine mounted to the working machine, comprising:

an exhaust system of the engine outputting exhaust gas;

an exhaust gas purification device comprising a catalyst and a soot filter, the exhaust gas purification device being configured to be mounted to the engine and being coupled to the exhaust system of the engine so as to receive the exhaust gas;

an intake air throttle that determines an amount of air to be input to the engine;

an exhaust gas throttle that determines an amount of exhaust gas to be input to the exhaust gas purification device;

a controller that determines a clogged state of the soot filter, that controls the intake air throttle, that controls the exhaust gas throttle, and that has a renewing mode during which either one or both of the air intake throttle and exhaust gas throttle are controlled in a manner that increases temperature of the exhaust gas to a degree allowing particulate matter clogging the soot filter to be burned in the soot filter and exhausted from the exhaust gas purification device,

a rotating speed holding switch having a first switch state in which an input is provided to the controller indicating that the controller is to hold a rotating speed of the engine and inhibit said renewing mode, even when the controller is already in said renewing mode.

2. The exhaust gas purification system of the working machine according to claim 1, wherein when the controller determines that the soot filter is clogged at or beyond a critical level the controller enters the renewal mode, even when the rotating speed holding switch is in said first switch state.

3. The exhaust gas purification system of the working machine according to claim 2, further comprising renewal advance notifying means which is actuated when the controller determines that the soot filter is clogged at or beyond the critical level.

4. The exhaust gas purification system of claim 1, wherein the renewing mode comprises a first renewing mode and a forced renewing mode different from the first renewing mode, and wherein during said forced renewing mode the controller is configured to control a post injection of fuel to the engine so that fuel is supplied into the exhaust gas purification device through the exhaust system causing burning of fuel in the exhaust gas purification device and burning of the particulate matter clogging the soot filter.

5. The exhaust gas purification system of claim 4, wherein the controller enters the forced renewing mode when the controller determines that the soot filter is clogged at or beyond the critical level.